Project Summary: Malaria is an important public health problem in China. The World Health Organization estimated that the annual number of malaria cases in China was about 740,000 in 2003. Malaria outbreaks often occur in central China. The mosquito Anopheles lesteri is the primary malaria vector in China and Korea, and it is highly susceptible to both Plasmodium vivax and P. falciparum. Despite the importance of A. lesteri in malaria transmission, little is known about the population genetics and ecology of this malaria vector species. The scantiness of research on A. lesteri population has been partly due to difficulties with its taxonomy and inadequate means of identifying the species. In the past several years we have developed a molecular identification method to distinguish A. lesteri from sibling species, thus enabling us to study the ecology and genetics of this important malaria vector. Preliminary studies suggest that the morphological characters, bionomics (such as host preference and larval habitat), and chromosomal karyotype of A. lesteri differ among populations from different geographic localities. The proposed research aims to improve our understanding of the population genetic structure and bionomics of A. lesteri in China. The 2 specific aims are: 1) To determine the population genetic structure of A. lesteri, and 2) To examine geographic variation in A. lesteri bionomics, including host-feeding preference and larval habitat selection. A unique aspect of this project is that it links the population genetics of A. lesteri with its ecology. The anticipated outcomes of this project include a better understanding of the ecology and genetics of A. lesteri mosquitoes as well as the geographic variation of its bionomics. This information is particularly useful for the design of rational area-specific vector control methods. [unreadable] [unreadable]